1. Field of the Invention
The present invention relates to hinge devices suitable for application to apparatuses, such as a mobile phone, a personal handyphone system (PHS), a personal digital assistant (PDA), a portable game machine, and a notebook personal computer, each including two bodies connected to each other with a hinge so as to be openable and foldable together, and also relates to methods of redirecting loads applied to the hinge devices, and to mobile terminal apparatuses.
In particular, the present invention relates to a hinge device including a stopper and a stopper-receiving portion that are configured such that a load produced upon contact therebetween when the two bodies are opened is redirected in such a direction that the thickness of the stopper becomes larger, whereby the strength of the hinge device is increased, and also relates to a method of redirecting the load applied to the hinge device, and to a mobile terminal apparatus.
2. Description of the Related Art
Nowadays, foldable mobile phones are gaining popularity. A typical foldable mobile phone includes an upper body and a lower body that are connected to each other with a hinge device and are thus openable and foldable together. There are some cases where a hinge device enabling the upper body and the lower body to be opened and folded together is integrally provided with the two bodies. Such a hinge device, provided as a portion of the two bodies in terms of design and shape, may limit the designs and shapes of the upper and lower bodies.
Therefore, most of the recent mobile phones employ a so-called “frame hinge device”, which is provided separately from the upper body and the lower body. With the frame hinge device, which is a separate body from the upper and lower bodies, the shapes of the upper and lower bodies can be designed substantially freely and with more ease.
The frame hinge device includes a first hinge member and a second hinge member. The first hinge member is secured to the upper body, and the second hinge member is secured to the lower body, whereby the upper and lower bodies are openable and foldable together. In a case where the rotation angle formed between the upper body and the lower body is regulated to be the maximum at a point at which the upper body and the lower body come into contact with each other when opened, respective contact portions of the upper body and the lower body are easily damaged. Therefore, the frame hinge device includes a stopper so that the rotation angle formed between the upper body and the lower body is regulated to be the maximum immediately before the upper body and the lower body, when opened, come into contact with each other. Such a stopper is easily damaged by, for example, an impact caused by dropping the phone and excessive opening of the phone. Therefore, in a product development process, developers make special efforts to provide sufficient strength to the stopper.
Japanese Unexamined Patent Application Publication No. 2006-118178 discloses a biaxial hinge that is not easily damaged and whose stopper is prevented from coming off a turning-movement shaft even if the sizes of the turning-movement shaft and the stopper are reduced. In this biaxial hinge, the stopper and the turning-movement shaft are formed as an integral body, and the turning-movement shaft included in the integral body is attached to an opening/closing-movement shaft. The turning-movement shaft is prevented from turning beyond the critical angle by causing a projection provided on the stopper to be locked by a locking portion of the opening/closing-movement shaft.
Since the turning-movement shaft and the stopper are provided as an integral body, sufficient strength can be provided to the stopper and the joint between the stopper and the turning-movement shaft. In addition, coming off of the stopper and damage to the stopper can be prevented from occurring while the turning-movement shaft is turned.